Pneumatic door lock

ABSTRACT

The invention concerns a lock for doors or operationally similar structures, the lock mechanism being manually actuated with the aid of pneumatic means, without the need for external energy. Means for manually producing overpressure are rigidly connected to a door. Further means are provided for converting the overpressure into a mechanical movement of parts of the closure mechanism, such that there is no longer any force-locking connection between the door and a counterpart in the door frame whereby the door can be opened.

BACKGROUND OF THE INVENTION

The current invention relates to a lock for doors or operationallysimilar structures, in which the mechanism is manually actuated with theaid of pneumatic means.

The application of pneumatic methods in locking mechanisms is knownchiefly for the turning or sliding of the door itself, such as presentedfor instance in U.S. Pat. No. 4,901,474. Solutions for the actuation ofthe moving parts of a lock only, using the application of compressedair, have also been suggested. Common to all these solutions is that thelocking mechanisms require the importation of external energy.

In U.S. Pat. No. 4,021,066 a pneumatic door bolting system for lorriesor railway wagons is proposed; in these vehicles compressed air is as arule immediately available for braking. The lock proposed in U.S. Pat.No. 4,169,616 requires an air pressure line to the lock from an externalsource, with which an expensive transmission part from the fixed doorframe to the moving door is provided. This applies similarly for thelocking system proposed in U.S. Pat. No. 4,691,948. The solutions quotedare based on the supply of external energy, because the manuallyachievable short-term pneumatic energy is small and is not sufficient toovercome the substantial friction forces, which arise in the opening ofconventional door locks.

SUMMARY OF THE INVENTION

The objective, which is addressed by the current invention, is to find alock for doors and operationally similar structures, such as, forexample, windows or sliding doors, whose mechanism is actuated with theaid of pneumatic means, without the requirement for external supply ofenergy.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross section of a first embodiment of the pneumatic doorlock according to the invention.

FIG. 2 is a cross section of a second embodiment of the pneumatic doorlock according to the invention.

FIG. 3 is a schematic diagram of the pneumatic connections in furtherforms of construction of the pneumatic door lock.

DETAILED DESCRIPTION

In FIG. 1 is given the schematic cross section through a firstembodiment of the pneumatic door lock. In a non-moving door frame, fromwhich only that part of the door frame 1 is shown, which lies adjacentto the lock, a door 2 is mounted, which is pivoted so as to swivel abouta (not shown) vertical axis. Means for the generation of pressure areincorporated in the door 2. These means, comprise a door handle 3, whichis firmly fixed to the door 2, in which a hollow body 4 is incorporated,which can be manually compressed, so that its internal volume isdecreased. The hollow body 4 here comprises a balloon made of rubber orplastic material. In the sense of the invention it can, however,comprise parts which are sealed one to the other fitting into each otherin a telescopic manner. The hollow body 4 is joined in an airtightmanner via a primary connecting tube 5 to an actuator 30, which convertsthe pressure into a mechanical movement. This is, as are the other partsof the locking mechanism, built in to the inner part of the door 2, forinstance in a (not shown) housing, such as is known from conventionallocks. In this form of construction the actuator 30 comprises a pressurecylinder 6, a piston 7 which can be moved in it and a piston rod 8 whichis fixed to it and guided essentially along a straight line. In afurther embodiment, not shown, the actuator 30 comprises a bellows ofmetal or an elastomer. A longitudinal locking bolt 12 is joined at oneend firmly to the piston rod 8 and arranged similarly to be movablealong the same straight line. Its other end advantageously includesmeans by which frictional forces can be minimized. These means comprisehere for example a suitable spring-supported first roller race 14; otherfriction reducing means are however also possible, for instance the useof special low friction and low wear materials, or the application ofsufficient lubricating grease materials between parts which slide oneach other.

A rotating bolt 15 is positioned about a turning axis 16 fixed firmly tothe door so that it can turn within an angular region defined by stopsto an order of magnitude of some 45°. An outer part of the rotating bolt15 extends out of the lock against a part of the door frame 1. Thisouter part similarly includes means for reducing frictional forces,which comprise here a spring-supported second roller race 19. Here also,as already mentioned in the case of first roller race 14, otherfriction-reducing means are possible. An inner part of the rotating bolt15, lying on the other side of the turning axis 16, includes twonotches: a locking notch 17 and a detent notch 18, in which the lockingbolt 12 engages in the locked or opened position respectively. A firstspring 20 is connected by pressure to the door 2 and the locking bolt 12under compression and ensures that the locking bolt 12 is always pressedagainst the rotating bolt 15 with the force of this first spring 20. Thefirst spring 20 is in this example inside the pressure cylinder 6 and isin compression contact with the pressure cylinder 6 and the pressurepiston 7. A counterpart 21 is firmly fixed to the door frame part 1 andoffers space with the door 2 shut for the outer part of the rotatingbolt 15 in a recess, not shown.

The lock functions in the following manner: with the door 2 shut, theouter part of the rotating bolt 15 lies under pressure in the recess ofthe counterpart 21. The locking bolt 12 is pressed by the first spring20 into the locking notch 17 of the rotating bolt 15 and fixes this, andthus the whole door 2, in this position by force. To open the door 2 thehandle 3 is grasped with one hand and the hollow body 4 compressed atthe same time. Due to the deformation of the hollow body 4 its internalvolume is decreased, whereby an overpressure arises in this volume. Thisoverpressure is transmitted via the primary connecting tube 5 into thepressure cylinder 6 and exerts there a pressure force on the pressurepiston 7. The pressure piston 7 is, together with the locking bolt 12firmly attached to it, pushed along its axis against the force of thefirst spring 20 away from the rotating bolt 15. The locking bolt 12thereby frees the locking notch 17, whereby the rotating bolt 15 is nolonger limited in its rotational movement. The force of the hand on thedoor knob 3, which is still maintained, now opens the door 2, wherebythe counterpart 21 turns the rotating bolt 15 so far that the firstroller race 14 snaps into the detent notch 18 and stops the rotatingbolt 15 in this new position, which corresponds to the open door.

The door can, as with conventional door locks, be easily closed againsimply by pulling or pushing it against the door frame section 1. Thecounterpart 21 in the door frame section 1 thereby captures the secondroller race 19 of the rotating bolt 15 and turns it back into itsstarting position. In doing so, a light resistance has to be overcome atthe first roller race 14, which at the start of the rotation is turnedaway from the detent notch 18. As soon as the door 2 lies completelyagainst the door frame section 1, the first spring 20 pushes the lockingbolt 12 back into the locking notch 17 of the rotating bolt 15, wherebythe door 2 is again locked.

Fire safety means are shown in FIG. 1. These comprise here a springblock 27, which is embedded at its one end in the door 2 and at itsother end lies on an additionally provided protrusion 26 of the lockingbolt 12. The spring block 27 includes a second spring 31, precompressedunder pressure and cast into a readily melting plastic material, andwhich is in particular stronger than the first spring 20, to which it isessentially opposed in parallel. Under great heat the plastic materialof the spring block 27 melts, whereby the second spring 31 presses onthe protrusion 26 of the locking bolt 12. The locking bolt 12 is therebypushed away against the force of the first spring 20, whereby therotating bolt 15 is released. In this manner it is assured that the door2 does not remain locked in the event of a fire in the building, evenfollowing a partial or complete destruction, caused by heat, of thepneumatic system. These fire safety measures are insignificant for thenormal functioning of the lock and can even be left out.

FIG. 2 shows a schematic cross section through a second form ofconstruction of the pneumatic door lock. It differs from the form ofconstruction described in FIG. 1 chiefly in that it includes a forceconversion. This is achieved here in the following manner: the pistonrod 8 has at its end a hinged joint 9 rotating about a vertical axis.The piston rod 8 is jointed non-positively to this joint 9 to one end ofa conversion rod 11, which is positioned in a swivelling manner on theguide axis 10, which is firmly fixed to the door. At its other end theconversion rod 11 engages in a cut out 13 in the horizontally movableguided locking bolt 12. A compressed alternative first spring 29replaces the first spring 20 described under FIG. 1. This is connectedat one end to the locking bolt 12, and at the other end to the door 2.The remaining parts of the lock correspond to the device alreadydescribed under FIG. 1, with the main difference being the movement ofparts of the actuator 30, for instance, the piston rod 8, via the hingejoint 9 first turns the conversion rod 11 about the guide axis 10through an angle in the order of magnitude of some 200 degrees. In doingso, its other end, which engages in the cut out 13 in the locking bolt12, pushes the locking bolt 12 against the resistance of the alternativefirst spring 29 away from the rotating bolt 15, whereby this isreleased. The directions of movement in space of individual parts of thelock mechanism (6-20) are not material to the invention. They can befreely chosen according to practical considerations. Thus, for instance,the guide axis 10 can also lie horizontally.

The fire safety provision shown in FIG. 1 and in the description of thisfigure is not shown in FIG. 2. It can also be integrated in thisembodiment.

FIG. 3 shows schematically an embodiment of the pneumatic means andconnections according to the invention, which allows a door 2 providedwith the lock to be opened from both sides and also to be locked from atleast one side, with the aid of known mechanical means. On each side ofthe door 2 there is a door handle 3, each with a hollow body 4 and eachhaving a primary connecting tube 5 provided. A connecting piece 24 withfour connections is connected to these two primary connecting tubes 5.Its third connection is connected with secondary connecting tubes 22first with the locking valve 25 and then with the actuator 30. Thefourth connection of the connecting piece 24 is connected via asecondary connecting tube 22 to an vacuum relief valve 23.

Mechanical means, with which the locking valve 25 can be opened, areprovided on at least one side of the door 2 and connected to the lockingvalve 25. These mechanical means, not shown, may comprise a commerciallyavailable closing cylinder, built into the door 2. If the key belongingto the closing cylinder is turned, the locking valve 25 opens and allowsthe air to escape so that the pressure cylinder 6 cannot be actuated.The vacuum relief valve 23 serves to ventilate the pneumatic systemagain after an actuation of the lock.

In a simplified embodiment, not shown, the mechanical means of lockingthe lock and the locking valve 25 are dispensed with; the thirdconnection of the connecting piece 24 is connected directly to theactuator 30.

In a further embodiment, not shown, an additional quick closing valve(not shown) is built in to one of the connecting lines 22, for instancebetween the connecting piece 24 and the locking valve 25. The quickclosing valve can advantageously only be operated from the inside of thedoor 2. Thus, as required, the pneumatic connection between the actuator30 and the hollow body 4 is again interrupted whereby the door 2 can nolonger be opened from the other side, even with the correct key.

What is claimed is:
 1. A lock for a door and frame structure comprisinga locking mechanism for attachment to said door or frame section and acounterpart for attachment to the opposing one of said door or framesection, whereby in the closed condition a pressure locked connectionexists between the locking mechanism and the counterpart, theimprovement comprising:an airtight hollow body (4) is provided, manuallycompressible and thereby reducible in its internal volume, with which anexcess pressure can be created manually, the locking mechanism (6-20)includes an actuator (30) for the conversion of an overpressure into amechanical movement of parts (12, 15) of the locking mechanism (6-20)and this actuator (30) is connected to the hollow body (4) by at leastone primary connecting tube (5), by movement of parts (12, 15) of thelocking mechanism (6-20) the pressure locked connection between thelocking mechanism (6-20) and the counterpart (21) is removed, theactuator (30) comprises a pressure cylinder (6), a pressure piston (7)which can move within it and a similarly movable piston rod (8)connected to it, the locking mechanism (6-20) includes a locking bolt(12) which slides linearly along its axis, the locking bolt (12) is inpressure locking contact with a movable part (8) of the actuator (30),the locking mechanism (6-20) includes a rotating bolt (15) which isassembled so that it can turn through a determined angular region, therotating bolt (15) is in pressure locking contact with the counterpart(21) during the meeting of the locking mechanism and the counterpart,the rotating bolt (15) includes a locking notch (17) and a detent notch(18), wherein the counterpart (21) captures a part of the rotating bolt(15) extending out of the lock and turns it so that the detent notch(18) comes to rest adjacent to the locking bolt (12) during theseparation of the locking mechanism and the counterpart, wherein thecounterpart (21) again captures the extending part of the rotating bolt(15) and turns it so that the locking notch (17) comes to rest adjacentto the locking bolt (12) during the meeting of the locking mechanism andthe counterpart, a first spring (20,29) is present, which is in pressurecontact with the locking bolt (12), when the locking mechanism isengaged in the counterpart, the first spring (20,29) pushes the lockingbolt (12) into the locking notch (17) and thereby fixes the rotatingbolt in this position by pressure locking, when the locking mechanism isdisengaged from the counterpart, the first spring (20,29) pushes thelocking bolt (12) into the detent notch (18) and thus holds the rotatingbolt (15) in a stable position but where the rotating bolt (15) can beforced out of the stable position, one end of the locking bolt (12)includes means (14) to reduce frictional resistance, the rotating bolt(15) includes means (19) for reducing fictional resistance at its enddirected against the counterpart (21).
 2. A lock for a door and framestructure comprising a locking mechanism for attachment to said door orframe section and a counterpart for attachment to the opposing one ofsaid door or frame section, whereby in the closed condition a pressurelocked connection exists between the locking mechanism and thecounterpart, the improvement comprising:an airtight hollow body (4) isprovided, manually compressible and thereby reducible in its internalvolume, with which an excess pressure can be created manually, thelocking mechanism (6-20) includes an actuator (30) for the conversion ofan overpressure into a mechanical movement of parts (12, 15) of thelocking mechanism (6-20) and this actuator (30) is connected to thehollow body (4) by at least one primary connecting tube (5), by movementof parts (12, 15) of the locking mechanism (6-20) the pressure lockedconnection between the locking mechanism (6-20) and the counterpart (21)is removed, wherein the actuator (30) comprises a bellows, the lockingmechanism (6-20) includes a locking bolt (12) which slides linearlyalong its axis, the locking bolt (12) is in pressure locking contactwith a movable part (8) of the actuator (30), the locking mechanism(6-20) includes a rotating bolt (15) which is assembled so that it canturn through a determined angular region, the rotating bolt (15) is inpressure locking contact with the counterpart (21) during the meeting ofthe locking mechanism and the counterpart, the rotating bolt (15)includes a locking notch (17) and a detent notch (18), wherein thecounterpart (21) captures a part of the rotating bolt (15) extending outof the lock and turns it so that the detent notch (18) comes to restadjacent to the locking bolt (12) during the separation of the lockingmechanism and the counterpart, wherein the counterpart (21) againcaptures the extending part of the rotating bolt (15) and turns it sothat the locking notch (17) comes to rest adjacent to the locking bolt(12) during the meeting of the locking mechanism and the counterpart, afirst spring (20,29) is present, which is in pressure contact with thelocking bolt (12), when the locking mechanism is engaged in thecounterpart, the first spring (20,29) pushes the locking bolt (12) intothe locking notch (17) and thereby fixes the rotating bolt in thisposition by pressure locking, when the locking mechanism is disengagedfrom the counterpart, the first spring (20,29) pushes the locking bolt(12) into the detent notch (18) and thus holds the rotating bolt (15) ina stable position but where the rotating bolt (15) can be forced out ofthe stable position, one end of the locking bolt (12) includes means(14) to reduce frictional resistance, the rotating bolt (15) includesmeans (19) for reducing frictional resistance at its end directedagainst the counterpart (21).
 3. A lock for a door and frame structurecomprising a locking mechanism for attachment to said door or framesection and a counterpart for attachment to the opposing one of saiddoor or frame section, whereby in the closed condition a pressure lockedconnection exists between the locking mechanism and the counterpart, theimprovement comprising:an airtight hollow body (4) is provided, manuallycompressible and thereby reducible in its internal volume, with which anexcess pressure can be created manually, the locking mechanism (6-20)includes an actuator (30) for the conversion of an overpressure into amechanical movement of parts (12, 15) of the locking mechanism (6-20)and this actuator (30) is connected to the hollow body (4) by at leastone primary connecting tube (5), by movement of parts (12, 15) of thelocking mechanism (6-20) the pressure locked connection between thelocking mechanism (6-20) and the counterpart (21) is removed, wherein atleast one valve (25) is present and is connected by airtight means viasecondary tubes (22) in series between the at least one hollow body (4)and the actuator (30), wherein a mechanical means is connected to eachof said at least one valves (25) for opening said valve, and whereinopening of at least one valve (25) interrupts the transmission of theoverpressure in the secondary tubes (22) to the actuator (30), thelocking mechanism (6-20) includes a locking bolt (12) which slideslinearly along its axis, the locking bolt (12) is in pressure lockingcontact with a movable part (8) of the actuator (30), the lockingmechanism (6-20) includes a rotating bolt (15) which is assembled sothat it can turn through a determined angular region, the rotating bolt(15) is in pressure locking contact with the counterpart (21) during themeeting of the locking mechanism and the counterpart, the rotating bolt(15) includes a locking notch (17) and a detent notch (18), wherein thecounterpart (21) captures a part of the rotating bolt (15) extending outof the lock and turns it so that the detent notch (18) comes to restadjacent to the locking bolt (12) during the separation of the lockingmechanism and the counterpart, wherein the counterpart (21) againcaptures the extending part of the rotating bolt (15) and turns it sothat the locking notch (17) comes to rest adjacent to the locking bolt(12) during the meeting of the locking mechanism and the counterpart, afirst spring (20,29) is present, which is in pressure contact with thelocking bolt (12), when the locking mechanism is engaged in thecounterpart, the first spring (20,29) pushes the locking bolt (12) intothe locking notch (17) and thereby fixes the rotating bolt in thisposition by pressure locking, when the locking mechanism is disengagedfrom the counterpart, the first spring (20,29) pushes the locking bolt(12) into the detent notch (18) and thus holds the rotating bolt (15) ina stable position but where the rotating bolt (15) can be forced out ofthe stable position, one end of the locking bolt (12) includes means(14) to reduce frictional resistance, the rotating bolt (15) includesmeans (19) for reducing frictional resistance at its end directedagainst the counterpart (21).
 4. A lock according to any one of claims1, 2, or 3, whereina fire safety means (27, 31) including a spring block(27) is present, the spring block (27) contains a pre-compressed secondspring (31), the second spring is cast into a material, which will meltas a result of temperatures encountered during a fire, the locking bolt(12) includes a protrusion (26) the spring block (27) is positioned sothat the second spring exerts a force on the protrusion (26) after themelting of the material, this force is sufficient to move the lockingbolt (12) against the resistance of the first spring (20, 29) so that itreleases the rotating bolt (15).
 5. A lock according to any one ofclaims 1, 2, or 3, whereinbetween the actuator (30) and the locking bolt(12) a mechanical power converter (9, 10, 11, 13) is present, which hasa hinge joint (9), a guide axis (10) and a conversion rod (11), thelocking bolt (12) has a cut out (13), the conversion rod (11) is joinedin a hinged manner at one end via the hinge joint (9) to a movable part(8) of the actuator (30), the conversion rod (11) is assembled so thatit can turn within a determined angular region about the guide axis(10), the other end of the conversion rod (11) engages in the cut out(13) of the locking bolt (12).
 6. A lock according to claim 5, whereinafire safety means (27, 31) including a spring block (27) is present, thespring block (27) contains a pre-compressed second spring (31), thesecond spring is cast into a material, which will melt as a result oftemperatures encountered during a fire, the locking bolt (12) includes aprotrusion (26) the spring block (27) is positioned so that the secondspring exerts a force on the protrusion (26) after the melting of thematerial, this force is sufficient to move the locking bolt (12) againstthe resistance of the first spring (20, 29) so that it releases therotating bolt (15).